Sediment Provenance Analysis and Paleogeography of Lower Paleozoic Basins in Northwestern South America

Mauricio Ibanez-Mejia
Department of Geosciences, University of Arizona Tucson, Arizona, USA
[email protected]

The Neoproterozoic to Paleozoic sedimentary sequences of northern South America have the potential of being important oil- and gas-producing horizons, and they are recently becoming the focus of active resource exploration by the energy industry. However, since most of these sequences are buried beneath the modern Andean foreland, very little is known about their stratigraphy, age, and the nature/timing of the main tectonic events that shaped these pre-Andean basins. The main objective of this project is to shed light into these issues by studying the sedimentary provenance of Neoproterozoic and Paleozoic units in northwestern South America using U-Pb geochronology and Lu-Hf isotope chemistry in detrital zircons. We have collected core samples from Ediacaran through Devonian sedimentary rocks of the southern Llanos basin, obtained from deep exploratory wells that have drilled below the Mesozoic unconformity in the area. In addition to providing first-order insights into basin paleogeography, tectonic evolution and feasible paleo-drainage configurations, the provenance signatures obtained from this autochthonous Amazonian margin will prove extremely useful to explore potential correlations that may exist with other Paleozoic sequences that appear exposed in the north Andean cordilleran massifs.

AAPG Search and Discovery Article #90157©2012 AAPG Foundation 2012 Grants-in-Aid Projects